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J K Duguid

Publications and source records attributed to J K Duguid.

At least 37 records · Page 2Linked to original sources
PubMed1993

Molecular genetic analysis of the ABO blood group system: 4. Another type of O allele.

We have encountered an allele which seems to be another type of O allele at the human histo-blood group ABO locus. We have determined the nucleotide sequence of this allele over the coding region in the last two coding exons. This allele does not possess the single-nucleotide deletion found common among all the O alleles previously analyzed. Compared with A1 allele, this allele has three nucleotide substitutions resulting in two amino acid substitutions. The introduction of these amino acid substitutions into the A1 transferase expression construct apparently abolished the enzymatic activity of A1 transferase.

ABO Blood-Group System↗
PubMed1993

Red cell antibody screening and identification: a comparison of two column technology methods.

Two commercial column techniques for use in antibody screening and identification procedures were tested in parallel with 1000 random samples sent for ante-natal serological investigation. The DiaMed ID microtyping system uses a sephadex gel contained in microtubes, either neutral or impregnated with anti-human globulin (AHG), for use in two-stage enzyme methods and LISS indirect antiglobulin testing (IAT) respectively. The Ortho Biovue technique consists of a slurry of micro glass spheres which act as the filter to retain haemagglutination reactions within the matrix. Columns containing AHG also possess a macromolecular density barrier to prevent test serum from passing into the column and neutralising the AHG. Both systems offer the advantage of 'no-wash' IAT, which minimises the potential for problems and errors associated with conventional spin-tube techniques. In this comparison of the two column methods, antibody detection rates were found to be similar and the sensitivity of both methods was comparable, although the Biovue technique was prone to exhibit equivocal results, particularly in the IAT.

Antibodies↗
PubMed1992

Effective concentration of bone marrow mononuclear cells using density gradient separation within an automated cell separator.

An effective method for concentrating bone marrow is described. Concentration was achieved using an intermittent flow cell separator. Elimination of mature haemopoietic cells was enhanced by the addition of a density separation medium (Ficoll-metrizoate) which was then removed by washing. All procedures were undertaken using the cell separator, this allowed for standardization of procedure and less manipulation which is associated with enhanced mononuclear cell recovery and less risk of microbial contamination. Mature granulocytes were depleted by 86.8% and red cells by 97.7% whilst mononuclear cells showed a 49% recovery. Marrows processed in this way and subsequently purged and/or cyropreserved were shown to successfully engraft when reinfused.

Bone Marrow Transplantation↗
PubMed1992

A method for clinical purging of myeloma bone marrow using peanut agglutinin as an anti-plasma cell agent, in combination with CD19 monoclonal antibody.

Previous studies have shown that the lectin peanut agglutinin (PNA) binds bone marrow plasma cells in the majority of patients with myeloma and does not bind to normal haemopoietic progenitors. This lectin has been used in combination with anti-CD19 monoclonal antibody (moAb) in a system for purging myeloma bone marrow. This has now been scaled up for application to ex vivo treatment of large volumes of bone marrow suitable for autologous bone marrow transplantation. Four bone marrow harvests from patients with myeloma containing 9.5 +/- 4.9% plasma cells were depleted of erythrocytes and mature granulocytes by Ficoll separation using the Haemonetics V50 cell separator. The mononuclear fraction was then purged with magnetic beads coated with PNA and anti-CD19 moAb. The system proved highly efficient with removal of all detectable plasma cells and CD19+ cells. Average mononuclear cell recovery following purging was 71% of the concentrated marrow with 78% yield of CFU-GM. Normal progenitor recovery related to patients' weight is predicted to be adequate for haemopoietic reconstitution following ablative chemoradiotherapy. This system is therefore feasible for large-scale clinical purging.

Adult↗
PubMed1991

Immunisation of staff of a regional blood transfusion centre with a recombinant hepatitis B vaccine.

Medical, nursing, laboratory and other staff of the Mersey Regional Blood Transfusion Centre at risk of acquiring hepatitis B were vaccinated against the virus with a recombinant vaccine. Altogether, 86% staff developed greater than 10 mIU/ml antibody to hepatitis B virus surface antigen after immunisation but the proportion was lower in older staff. After a further injection of vaccine was given to poor and non-responders the overall proportion responding rose to 93%. The difference in response between the sexes was significant. Women had a higher rate of response and, among those persons responding, women developed a higher concentration of antibody.

Adult↗
PubMed1991

Continuous flow cell separator use for bone marrow processing.

Many techniques have been described for processing bone marrow prior to transplantation, purging or cryopreservation. Effective techniques incorporate centrifugation and, or, density separation to produce an ideal marrow concentrate. We report on the use of a continuous flow cell separator (COBE Spectra) for marrow processing. Preliminary results indicate that the improved technology incorporated in this machine together with the new algorithm control of its collection functions allows for rapid collection of an ideal marrow concentrate. The addition of an inert sedimenting agent prior to processing enhances differential mononuclear cell collection and elimination of red blood cells and granulocytes. By this technique a volume depletion of 87% was achieved with recovery of 76.4% mononuclear cells and 86.5% CFU-GM progenitor cells. Marrow processed in this manner has been successfully transplanted; patients receiving such marrow show no delay in engraftment and their grafts have been sustained.

Bone Marrow Cells↗
PubMed1991

Evaluation of the ID-gel test for antibody screening and identification.

A gel technique for the detection of red blood cell (rbc) antigen-antibody reactions was evaluated for use in antenatal antibody screening and identification procedures. The evaluation was undertaken on 3,900 random antenatal samples. Results obtained in the gel test system were compared with those obtained from parallel testing using conventional serological methods. The ID gel system detected 148 (3.7%) red cell antibodies, compared with 95 (2.4%) using traditional techniques. The number of non-specific antibodies and false-positive screens were reduced using the gel test system. Antibody titres performed using the gel system were more sensitive than with our tube IAT method. The gel system was easy to use and gave reliable, reproducible results. Antibody detection rates were enhanced compared with our existing routine techniques.

Blood Grouping and Crossmatching↗
PubMed1991

Clinical evaluation of the effects of storage time and irradiation on transfused platelets.

Platelet concentrates stored for up to 5 days at room temperature or irradiated with 15 Gy immediately prior to transfusion were evaluated for their ability to increase the platelet count in thrombocytopenic patients. Platelets irradiated with a dose of 15 Gy immediately prior to transfusion achieved corrected increments (CI) at 1 and 20 h after transfusion no different from those achieved by non-irradiated platelets. Storage for 5 days reduced the mean 1-hour CI to 5.7 compared with a mean of 12.3 achieved by platelets transfused after only 1-day storage (p = 0.008). Similarly, the frequency of a repeat transfusion being indicated within 24 h increased with increasing storage time (p = 0.005).

Blood Platelets↗
PubMed1991

Cold agglutinins in haemophiliac boys infected with HIV.

Eleven haemophiliac boys infected with HIV were screened for irregular red cell antibodies and were compared with nine haemophiliac boys who did not have antibodies to HIV. Seven (64%) of the children who had antibodies to HIV also had cold agglutinins, mostly of anti-I specificity, compared with one (11%) of those who did not have antibodies to HIV. The children with antibodies to HIV and cold agglutinins had a significantly increased mean IgM concentration. The presence of cold agglutinins was not correlated with T4 lymphocyte count, symptoms of HIV infection, serum beta 2 microglobulin concentrations, concentrations of IgG or IgA, or with the evidence of past infection with cytomegalovirus or Epstein-Barr virus.

Adolescent↗
PubMed1991

Blood group chimaerism: a possible further example.

A blood group chimaera is described whose red blood cells exhibit a dual population of group A1 and O, in the proportions 20% and 80% respectively. These results could also indicate a blood group mosaic of the Amos type, but family studies, secretor and transferase investigations on this patient suggest that blood group chimaerism of unestablished type is more likely. There was no further evidence of chimaerism found during cytogenetic investigations, immunoglobulin allotyping or studies of red cell enzyme systems. Blood group chimaeras were previously thought to be rare, as dual red cell populations and the resulting mixed-field agglutination patterns are not always easy to recognise. This case is the second example of chimaerism found within two years in a single routine laboratory, appearing to confirm the view that chimaerism is not as uncommon as previously thought.

ABO Blood-Group System↗
PubMed1990

Developing techniques in blood transfusion.

Expansion of transfusion medicine has led to an increasing awareness of the importance of its practice. Specialists in this branch of haematology whose main aim is to provide adequate and safe supplies of blood (and blood products) and to ensure these are used appropriately, are increasingly aware that to do this efficiently requires the development and utilization of new laboratory and technical procedures. Review of cross-matching techniques has led to the introduction of more rapid methods using low ionic strength saline. Use of monoclonal antibodies for blood grouping has made use of new technology, whilst allowing scarce human plasma to be used more appropriately for therapeutic purposes. Similarly, the implementation of a more rational approach to blood ordering, as in a maximum surgical blood-order schedule, allows for the more efficient use of donor blood. The use of microtitre plates for grouping and cross-matching techniques allows for speed and economy in the transfusion laboratory. Their use is also associated with increased automation and computer use. The possibility of using solid-phase techniques, monocyte-macrophage assays and antibody-dependent cellular cytotoxicity assays introduces new techniques differing markedly from time-honoured liquid-phase serology methods. The application of flow cytometry, which has already been shown to be useful in many aspects of haematology, is also of benefit in the field of blood transfusion science. Safety of blood transfusion is an important aspect of its practice and has led to the introduction and development of screening tests for donor blood to exclude infection risks from such organisms as HIV-1, hepatitis B and non-A, non-B hepatitis. Another approach to ensure the safety of transfused blood has been increased usage of autologous transfusion by means of both predeposit donation and intraoperative cell salvage.

Antibodies, Monoclonal↗
PubMed1990

Red cell antigens and renal transplantation.

Donor-specific transfusion was performed with and without cyclosporine between haplomismatched relatives prior to living-donor renal transplantation. Red cell antigen mismatching was not taken as a contraindication to DST. Of 80 patients included in the trial; eleven were ABO-mismatched, 15 were Rh(D)-mismatched, and a further 11 were transfused in the presence of atypical red cell antibodies (anti-D, -C, -Fya, -Kell -N, -H/I -I, -P1, -Wra). Patients were randomized to receive cyclosporine (10 mg/kg) daily during DST or not (control group). The presence of atypical red cell antibodies, with the exception of Rh anti-D, did not appear to influence DST or renal transplantation. DST did not act as a primary stimulus to Rh anti-D production but stimulated preexisting anti D levels. ABO mismatching did not appear to influence DST or subsequent renal transplantation except in one group A [corrected] patient who received group O [corrected] blood and cyclosporine. This patient developed a severe, but self-limiting, autoimmune hemolytic anemia due to auto-anti A antibodies. A similar group A patient in the control group developed an auto-antibody with no clinical sequelae. The influence of cyclosporine on the development of this auto-antibody is uncertain. We conclude that, with the exception of preexisting anti-D antibodies, minor red cell antigen disparities should not preclude pretransplant conditioning with donor-specific transfusions.

ABO Blood-Group System↗
PubMed1987

Oral administration of erythrocyte membrane antigen does not suppress anti-Rh(D) antibody responses in humans.

The effects of prior oral administration of erythrocyte membrane preparations (Oral Rh antigen) on the serum anti-Rh(D) antibody response has been evaluated in non-sensitized Rh(D)-negative male volunteers, and in female volunteers sensitized previously by Rh(D)-positive fetal blood during pregnancy. Sixty-one percent (11/18) of males who received oral Rh antigen (either D-positive or D-negative) before intravenous challenge with Rh(D)-positive cells produced detectable antibodies; of these 11, six received oral Rh(D)-negative antigen and five received oral Rh(D)-positive antigen. Seventy-two percent (13/18) of control males, who had received no prior oral Rh antigen, produced antibodies following challenge with Rh(D)-positive cells. Three out of six pre-sensitized females who received oral D-positive or D-negative Rh antigen for 4 weeks, but without intravenous challenge, increased their anti-Rh(D) antibody levels which peaked after 11-18 weeks: two had received Rh(D)-positive antigen, and one Rh(D)-negative antigen. These data indicate that administration of oral Rh antigen before parenteral immunization does not significantly suppress the anti-Rh(D) antibody response. Indeed, oral administration of either Rh(D)-positive or Rh(D)-negative antigen can boost systemic antibody in pre-sensitized females. These results do not support the rationale of treating Rh-sensitized pregnant women with oral Rh antigen.

Administration, Oral↗